Device for the separation of non-magnetizable metals and ferrous components from a solid mixture and method for operating such device

ABSTRACT

In an arrangement which including a motor-driven system for the separation of non-magnetisable metals, vibrations and resonances which generally are present in such arrangement, are eliminated. This is accomplished by utilizing a drum mounted on and rotating about a stator, within which a magnetic rotor fitted with permanent magnets is eccentrically arranged and mounted on said stator. The stator is provided with a balance weight for mass balance.

BACKGROUND OF THE INVENTION

The invention relates to a device with a system driven by a motor forseparating non-magnetizable metals, in particular non-ferrous metals,and ferrous fractions that are present, from a solid mixture, with adrum that is supported on a stator and rotates around the stator, with arotating magnet rotor fitted with permanent magnets eccentricallyarranged in the rotating drum and supported in the stator. The inventionalso relates to a method for operating the device.

DESCRIPTION OF THE RELATED ART

Such devices and methods for separating non-magnetizable metals areknown in the art.

For example, DE-C1-38 23 944 proposes a magnet system that is driveninside a belt drum with a rotation speed that is higher than therotation speed of the belt drum. The outside diameter of the magnetsystem is herein smaller than the unobstructed inside diameter of thebelt drum, and more importantly, the magnet system is arrangedeccentrically in the belt drum.

DE-C1-38 17 003 discloses an improvement of this device, whereby theposition of the eccentrically arranged magnet rotor in the quadrant ofthe material discharge zone and the effective range of the alternatingmagnetic field produced by the magnet rotor can be adjusted in theradial direction.

In order to improve the separation effect of the aforedescribed solidmixtures, after initial separation of the Fe-fraction, with respect tonon-ferrous metals, DE-C2-195 21 415 constructively combines severalconventional technical means, ranging from the feed regions of the solidmixture to the conveyor and discharge regions and the separation zonesformed by the trajectories, to improve the purity of the recoveredgraded concentrates of the various material fractions.

The search for precious materials in recycling operations is stillongoing and new problems have arisen.

When non-magnetizable metals, such as non-ferrous metals, are separatedfrom solid mixtures which are obtained after separation of theFe-fraction, for example from a shredder light fraction, the purity ofthe recovered graded non-ferrous metal fraction should be increased notonly to fetch a higher price, but also to economically separate massflows of solid mixtures into reusable fractions.

It has been observed in practice that the aforedescribed solid mixturesstill contain residual Fe - even after prior Fe-separation.

Processing mass flows of solid mixtures with the aforedescribed deviceshas led, among others, to the design of extremely wide drums and magnetrotors that are eccentrically arranged in the drums and rotate with thedrums. This causes oscillations which negatively impact both the systemstructure and the separation effect.

SUMMARY OF THE INVENTION

It is an object of the invention to provide a device of theaforedescribed type, which can meet the requirements for industry-scaleseparation of non-magnetizable metals and any remaining Fe-fractionsfrom solid mixtures, in particular after the Fe - fraction has beenseparated from the shredder light fraction. More particularly, thepurity of the recovered graded non-ferrous metals has to be guaranteed,while the remaining Fe-fractions still have to be separated. Aparticular problem to be solved is a reduction and possible eliminationof oscillations that occur in particular with extremely wide drums andpossibly also with the connected conveyor belt systems as well as theelimination of corresponding resonances in the structure. The relatedmethod is intended to ensure the purity if the recovered gradedconcentrates.

An assembly is disclosed including a system driven by a motor forseparating non-magnetizable metals, in particular non-ferrous metals,and ferrous fractions that are present, from a solid mixture, with adrum which is supported on a stator and which rotates around the stator.The system also includes a rotating magnet rotor fitted with permanentmagnets eccentrically arranged in the rotating drum and supported in thestator. The stator is provided with a balance weight for balancing themass. The balance weight is implemented as an oscillation damper. Thebalance weight also operates as an oscillation damper through adjustmentof the angle by tilting the magnet rotor which is arranged eccentricallyin the stator. In the region of the balance weight, a transport magnetis disposed for separating the Fe-fraction contained in the non-metals.The balance weight and the transport magnet form an assembly. Further,the balance weight may be a magnet.

The shape of the balance weight is such that it matches the shape of thedrum shell of the drum and the shape of the balance weight also ismatched to the shape of the magnetic field that is being generated. Thebalance weight may have a sickle-shaped cross-section perpendicular tothe axis of the drum.

The magnet rotor comprises permanent magnets which may have differentshapes, dimensions and polarities in both the radial and axial directionof the magnet rotor. The drum and the magnetic rotor, arrangedeccentrically in the drum, may be incorporated as a header drum in acontinuous conveyor belt system that conveys the solid mixture. At leastone separation apex is arranged subsequent to the device, wherein theseparation apex can be adjusted with the help of an adjusting device incooperation with a means, for example a camera, which recognizes thecorresponding composition of the separated fraction.

The speed of the drum is adjustable and the rotation speed of the magnetrotor is also adjustable. Both the angle of the magnet rotor, arrangedin the stator about the rotation axis of the drum as well as thedistance of the axis of the magnet rotor arranged in the stator relativeto the rotation axis of the drum, are adjustable.

A conveyor belt of the conveyor belt system has a guide projection whichis guided in a circumferential groove of the drum shell. The conveyorbelt system is divided by the circumferential projection into tworegions, with a dedicated separation.

The invention will be described herein after with respect to a complexembodiment, wherein different modifications of the device areillustrated which, when taken together, contribute to a solution of theproblem.

BRIEF DESCRIPTION OF THE DRAWINGS

The drawings show in

FIG. 1 a longitudinal cross-section through a drum with a magnet rotoreccentrically arranged in the drum and a balance weight according to theinvention,

FIG. 2 the cross-sectional view of FIG. 1 with the balance weightaccording to the invention and a transport magnet,

FIG. 3 a schematic diagram of the device in a conveyor belt system witha connected separation apex and means for adjusting the separation apex,

FIG. 4 a schematic diagram of the conveyor belt system with acircumferential projection disposed on the conveyor belt and associatedseparation apexes arranged subsequent to the conveyor belt regions, and

FIG. 5 a partial cross-section through a drum shell.

DESCRIPTION OF THE PRESENTLY PREFERRED EMBODIMENTS

As depicted in FIGS. 1 and 2, the device according to the inventionincludes a drum 2 which is supported on a stator 1 and rotates about thestator 1. A rotating magnet rotor 4 fitted with permanent magnets 3 iseccentrically arranged in the drum 2 and supported in the stator 1. Thefunctionality and operation of such device for separatingnon-magnetizable metals from a solid mixture is extensively described inthe references addressing the state-of-the-art.

Since the separation effect in such devices is produced by tilting themagnet rotor 4 that is eccentrically arranged in the stator 1, a balanceweight 1.1 is arranged on the stator 1 for mass balance. This balanceweight 1.1 simultaneously operates as an oscillation damper, inparticular when an extremely wide drum 2 and/or conveyor belt system 5,5.1 are used, as illustrated in FIGS. 3, 4 and 5.

To separate from the solid mixture the remaining Fe-fraction in additionto the usually separated non-ferrous metals, the balance weight 1.1 isimplemented as an assembly with a transport magnet 1.2 or as a magnet,wherein the shape of the balance weight 1.1 is matched to the shape ofthe drum 1.

To optimize the efficiency of the magnetic field and hence theseparation effect, the shape of the balance weight 1.1 is matched to theshape of the magnetic field to be generated, and can have atechnologically advantageous sickle-shaped cross-section.

Permanent magnets 3 of different shapes, dimensions and polarities inboth the radial and axial direction of the magnet rotor 4 canadditionally be fitted to the magnet rotor 4.

Such device implementation alone can satisfy the requirements forsolving the problems addressed by the invention.

If the drum 2 with the magnetic rotor 4 that is arranged eccentricallyin the drum is incorporated as a header drum in a continuous conveyorbelt system 5 with a conveyor 5.1 that conveys the solid mixture (FIGS.3, 4), followed by a separation apex, then a means 7, for example acamera, that recognizes the corresponding composition of the separatedfraction the separation apex 6 can be provided, wherein the means 7cooperates with an adjusting device 9 which adjusts the separation apex6 to a corresponding concentrated graded composition of the separatedfraction.

The separation effect is also enhanced in that

-   -   the rotation speed of the drum and    -   the rotation speed of the magnet rotor can be matched to the        flow rate and/or composition of the solid mixture and that both        the angle of the magnet rotor 4 about the rotation axis of the        drum 2 as well as the distance of the axis of the magnet rotor 4        relative to the rotation axis of the drum 2 can be adjusted to        obtain the desired trajectories for the non-ferrous metals to be        separated.

For a very wide conveyor belt system 5 and conveyor belt 5.1, it may beadvantageous for certain applications for separating solid mixtures todivide the conveyor belt system 5.1 into two regions with acircumferential projection 10, to arrange a dedicated separation apex6.1, 6.2 after these regions, and to adjust the separation apexes (6.1,6.2) independently of each other, so that different materials of solidmixtures can be subjected to pre-cleaning and post-cleaning.

As shown in FIG. 5, the conveyor belt 5.1 can be guided on aparticularly wide drum 2 and the conveyor belt 5.1 can be prevented fromleaving the running surface and/or the drum shell 2.1 on drum 2, byproviding (see FIG. 5) a bead-like guide projection 11 in the conveyorbelt 5.1. The guide projection 11 runs and is guided in acircumferential groove 12 of the drum shell 2.1.

To improve the separation quality, the upper edges of the separationapexes 6, 6.1, 6.2 can be implemented as a rotating cylinder (notshown).

In useful embodiments of the device of the invention, a stripping unit 8(FIG. 3) can be arranged on the outer shell 2.1 of the drum 2 to preventharmful fractioned particles from entering between the conveyor belt 5.1and the drum shell 2.1.

For practical industrial applications, it is important to provide amethod which guarantees the separation quality in the event of a powerfailure until the drive system comes to a halt. According to the methodof the invention, the energy of the still rotating magnet rotor 4 isused for the motor (not shown) to drive the conveyor belt system 5, inorder to drive the drum 2 with the other motor (not shown) of the magnetrotor 4 which now operates as a generator, long enough so that theremaining solid mixture, which was left on the conveyor belt system 4when the power failed, can be separated. The magnet rotor (4) arrangedin the stator (1) forms an angle about the rotation axis of the drum(2). said angle as well as a distance of the axis of the magnet rotor(4) arranged in the stator (1) relative to the rotation axis of the drum(2) are adjustable. The upper edge of the separation apexes (6.6.1.6.2)is implemented as a rotating cylinder for improving the separationquality.

INDUSTRIAL APPLICABILITY

The invention provides the industry with a device and a method forseparating non-magnetizable metals and Fe-fractions from a solidmixture, which in addition to a compact device configuration provides ahigh separation quality and purity of the recovered graded fractions.

1. A conveyor belt assembly including a motor-driven system forseparating non-magnetizable metals and ferrous fractions that arepresent, from a solid mixture, comprising a stator (1) and a drum (2)supported on the stator (1) for moving the conveyor belt, the drumrotating around the stator, a rotating magnet rotor (4) includingpermanent magnets, the rotating magnet rotor being eccentricallyarranged in the rotating drum (2) and supported on the stator (1), thestator (1) includes a balance weight (1.1) for providing mass balanceand operating as an oscillation damper, the balance weight supported onthe stator (1) and arranged in the rotating drum (2) a predetermineddistance away from the stator (1) and the balance weight (1.1)compensates for oscillations produced from tilting the magnet rotor (4).2. The assembly according to claim 1, wherein the balance weight (1.1)is shaped to match the shape of a magnetic field to be generated.
 3. Theassembly according to claim 1, wherein the balance weight (1.1) includesa sickle-shaped cross-section perpendicular to an axis of the drum (2).4. The assembly according to claim 1, wherein the magnet rotor (4)comprises permanent magnets (3) having a shape, dimension and polarityin both a radial and an axial direction of the magnet rotor (4).
 5. Theassembly according to claim 1, wherein the drum (2) and the magneticrotor (4) are formed as a header drum in a continuous conveyor beltsystem (5) that conveys the solid mixture.
 6. The assembly according toclaim 1, further comprising at least one separation apex (6) arrangedsubsequent to the assembly, wherein the separation apex (6) is adjustedby an adjusting device (9) in cooperation with a means for identifying(7) the composition of the separated ferrous fractions.
 7. The assemblyaccording to claim 1, wherein the rotating drum (2) has an adjustablespeed.
 8. The assembly according to claim 1, wherein the rotation of themagnet rotor (4) is adjustable.
 9. The assembly according to claim 1,wherein the magnet rotor (4) arranged on the stator (1) forms an angleabout the rotation axis of the drum (2), said angle as well as adistance of the axis of the magnet rotor (4) arranged in the stator (1)relative to the rotation axis of the drum (2) are adjustable.
 10. Theassembly according to claim 1, further comprising a transport magnet(1.2) disposed in a region of the balance weight (1.1) for separatingthe Fe-fraction contained in the non-metals.
 11. The assembly accordingto claim 10, wherein the balance weight (1.1) and the transport magnet(1.2) form a subassembly.
 12. The assembly according to claim 10,wherein the balance weight (1.1) is implemented as a magnet.
 13. Theassembly according to claim 1, wherein the rotating drum includes a drumshell (2.1) and wherein the balance weight (1.1) is matched in shape tothe drum shell (2.1).
 14. The assembly according to claim 13, furthercomprising a stripping unit (8) arranged on the drum shell (2.1) of thedrum (2).
 15. An assembly including a motor-driven system for separatingnon-magnetizable metals and ferrous fractions that are present, from asolid mixture, comprising a stator (1) and a drum (2) supported on thestator (1), the drum rotating around the stator, a rotating magnet rotor(4) including permanent magnets, the magnet rotor (4) beingeccentrically arranged in the rotating drum (2) and supported on thestator (1), the stator (1) includes a balance weight (1.1) for providingmass balance and operating as an oscillation damper, the balance weightsupported on the stator (1) and arranged in the rotating drum (2) apredetermined distance away from the stator (1) further comprising atleast one separation apex (6) arranged subsequent to the assembly,wherein the separation apex (6) is adjusted by an adjusting device (9)in cooperation with a means for identifying (7) the composition of theseparated ferrous fractions, wherein the identifying means is a camera.16. An assembly including a motor-driven conveyor belt system forseparating non-magnetizable metals and ferrous fractions that arepresent, from a solid mixture, comprising a stator (1) and a drum (2)supported on the stator (1), the drum rotating around the stator, arotating magnet rotor (4) including permanent magnets, the magnet rotor(4) being eccentrically arranged in the rotating drum (2) and supportedon the stator (1), the stator (1) includes a balance weight (1.1) forproviding mass balance and operating as an oscillation damper, thebalance weight supported on the stator (1) and arranged in the rotatingdrum (2) a predetermined distance away from the stator (1), wherein thedrum (2) and the magnetic rotor (4) are formed as a header drum in acontinuous conveyor belt system (5) that conveys the solid mixture andwherein a conveyor belt (5.1) of the conveyor belt system (5) has aguide projection (11) which is guided in a circumferential groove (12)of the drum shell (2.1).
 17. An assembly including a motor-driven systemfor separating non-magnetizable metals and ferrous fractions that arepresent, from a solid mixture, comprising a stator (1) and a drum (2)supported on the stator (1), the drum rotating around the round thestator, a rotating magnet rotor (4) including permanent magnetseccentrically arranged in the rotating drum (2) and supported in thestator (1), the stator (1) includes a balance weight (1.1) for massbalance, wherein the drum (2) and the magnetic rotor (4) are formed as aheader drum in a continuous conveyor belt system (5) that conveys thesolid mixture, wherein a conveyor belt (5.1) of the conveyor belt system(5) has a guide projection (11) which is guided in a circumferentialgroove (12) of the drum shell (2.1) and wherein the conveyor belt system(5.1) is divided by a circumferential projection (10) into two regions,with a dedicated separation apex (6.1, 6.2) associated with each ofthese regions and arranged after these regions, wherein the separationapexes (6.1, 6.2) are adjustable independent of each other, wherebydifferent materials of solid mixtures can be subjected to pre-cleaningand post-cleaning.
 18. The assembly according to claim 17, wherein theupper edge of the separation apexes (6, 6.1, 6.2) is implemented as arotating cylinder for improving the separation quality.